1. Field of the Invention
The present invention relates to a method for fabricating a semiconductor device, and more particularly to a method for fabricating a high voltage transistor.
2. Description of the Prior Art
Every electrical device has a particular working voltage and frequency condition; therefore, electrical devices and related passive elements utilized in the electrical devices, such as inductors, capacitors, resistors and transformers, act as a switch to determine the value of the voltage and the type of current thereof. High voltage transistors may also function as switches and are broadly utilized in CPU power supplies, power management systems, AC/DC converters, LCD/plasma TV drivers, automobile electronic components, PC peripheral devices, small DC motor controllers, and other consumer electronic devices.
A high-voltage transistor may include a gate, a channel formed under the gate, source/drain regions formed on both sides of the channel, and a drift region for distributing an electric field applied to the source/drain regions at the time a device is driven.
In high voltage applications, the transistor is designed to withstand high voltages. Due to their structural design, however, a current leakage problem may occur through the gate dielectric layer.